Alaska earthquakes

M3.5 earthquake 112 km SW of Adak, Alaska

A magnitude 3.5 earthquake struck 112 km SW of Adak, Alaska on Tue, Apr 18, 2023, 12:57 AM HADT (09:57 UTC), 35 km (22 mi) below the surface.

A larger quake followed: M5.3 135 km WSW of Adak, Alaska. This one was a foreshock.

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Where this earthquake was located, with the others nearby. Select one for its page.

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The earthquake

Magnitude: 3.5 (mb), minor
Local time: Tue, Apr 18, 2023, 12:57 AM HADT
UTC: 2023-04-18 09:57:29 UTC
Depth: 35.0 km (21.7 mi), shallow
Epicenter: 51.154° N, 177.773° W
Region: Alaska
Tsunami flag: No
Status: Reviewed by a seismologist

Did you feel it?

No one has reported feeling this quake to the USGS.

How well it is located

Reviewed by a seismologist.

Location uncertainty: About 3.4 km horizontally, 2.0 km in depth
Magnitude uncertainty: ±0.11
Depth from: Operator assigned
Station coverage gap: 196°, poorly surrounded by stations
Stations used: 46

Nearby

Within 100 km, magnitude 1.5 and up: at least 202 in the 60 days after this one and at least 200 in the 30 days before it.

After

The first 60 of at least 202.

Before

Earthquakes today Alaska earthquakes Live radar here

Sources

From the USGS Earthquake Hazards Program and its partner networks, event us6000k663 (also filed as ak0234yrqnzm). Read Wed, Sep 30, 2026, 4:25 PM UTC.